2017-08-10T19:35:41ZUnderstanding the adoption of additive manufacturinghttp://hdl.handle.net/1721.1/110892
Understanding the adoption of additive manufacturing
Garza, Jose M. (Jose Manuel Garza Estrada)
Additive Manufacturing (AM) -commonly known as 3d printing - is experiencing an upward trend as measured by a number of metrics, such as patent filing and number of company entries. The number of companies manufacturing hardware, software and materials serving both consumer and industrial segments of this industry has increased over recent years. This technology has radically changed how companies, designers and consumers in general go about prototyping their ideas. AM has also impacted low-volume manufacturing by allowing the production of small batches of products with all the advantages and flexibility the technology confers. Because the industry is still in its fluid phase, a high level of activity and significant changes are still to come. Employing Diffusion of Innovation theory by E.M. Rogers [1] which proposes the use of five factors or dimensions to assess the diffusion speed: relative advantage, compatibility, complexity, triability and observability; the study followed a two-pronged methodology. First I conducted semi-structured interviews and observational analysis; then, I analyzed technological developments, patent activity and firm entry. This study uncovers that 3d-printing something without observing technical requirements is quite easy. But 3d-printing a product that complies with a set of product requirements and specifications, so that the component can then be used in the context of a larger assembly or specific use, is quite another story. Based on observational data this thesis describes the vicissitudes of designing, selecting the printer, setting up the printer's parameters and ultimately printing a component, and thus demonstrates a perspective of the adoptability of this technology.
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2016.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 55-56).
2016-01-01T00:00:00ZOptimizing resource allocation in a portfolio of projects related to technology infusion using heuristic and meta-heuristic methodshttp://hdl.handle.net/1721.1/110145
Optimizing resource allocation in a portfolio of projects related to technology infusion using heuristic and meta-heuristic methods
Zuloaga, Maximiliano S. (Maximiliano Sebastian)
In today's competitive environment, manufacturing companies are under constant pressure to improve previous products or release new ones. Nonetheless, most products are not designed and built from scratch, but rather, are based on previous versions of the product with the addition of incremental improvements given by the infusion of new technologies. The objective of this research is to focus on continuous improvements where the level of required change is small to medium, which is the most common manner that companies use to achieve advancements in their products or systems. Most of the available literature related to project scheduling assumes that projects are non-iterative and do not consider rework in the analyzes. On the other hand, studies that analyze cyclical projects focus on product design and development, which usually requires a level of experimentation that makes them inherently different from advancements due to incremental improvements. At the same time, the literature on technology innovation is abundant and there are frameworks to assess the impact of transferring various technologies into existing products. However, there has not been proposed a method that specifically addresses the planning and scheduling process required to infuse technologies. Furthermore, the definitive selection for infusion cannot be applied without taking into account available resources, time required to mature technologies and the interaction among them. Portfolio selection and the scheduling process have usually been treated separately although they are interdependent in this particular case. Different plans can make quite different demands on system resources and its availability will impact the portfolio of selected technologies. This thesis intents to bridge the gap between the portfolio scheduling as well as processes for technology selection and insertion by taking a holistic approach, while the iterative nature of activities, due to rework, is included into the model. Therefore, methods for effectively allocating resources in a portfolio of projects related to technology infusion are recommended. Initially, a heuristic method is proposed based on priority rules. However, as the assumptions of the model are loosened a novel method is suggested that combines Genetic Algorithm (GA) and Artificial Bee Colony (ABC). Numerical results indicate that the hybrid meta-heuristic method based on GA-ABC is effective in finding good resource allocations while considering rework; which is shown, can affect the projects that comprise the portfolio and therefore is worthwhile planning for.
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2017.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 115-120).
2017-01-01T00:00:00ZUsing object process methodology to develop interfaces and smart electronic procedures for simulated telerobotic operationshttp://hdl.handle.net/1721.1/110144
Using object process methodology to develop interfaces and smart electronic procedures for simulated telerobotic operations
Yang, Yongkai Eugene
This thesis addresses two questions: 1) How should an existing space telerobotic simulator be extended to incorporate Smart Electronic Procedures (SEP)? 2) Are there benefits to using a single Object-Process Methodology (OPM; ISO 19540) from the field of system engineering as an alternative to the Task Analysis (TA) methods traditionally used in human factors engineering (HFE)? A NASA sponsored EP development project provided the opportunity to investigate. HFE traditionally supports analysis and design by using multiple Task Analysis (TA) methods, including Hierarchical TA (HTA), Tabular TA (TTA), and Abstraction Hierarchy (AH). But the three techniques combined neither defines all the necessary preconditions for each task to succeed nor produces an executable model of the entire system that can be simulated and tested for logical correctness, and results are presented in a form that can be difficult for others to comprehend. To evaluate OPM usefulness, a space telerobotic operation was analyzed using successive HTA, TTA and AH techniques, and compared with a corresponding OPM analysis. A single OPM model precisely specified the preconditions and post-conditions for all the processes and described the relationships between system objects-both human and non-human-and the processes in its hierarchy of Object-process Diagrams that translate on the fly to Object-Process Language - a subset of natural English. Advantages of OPM include its holistic approach, bimodal presentation, simplicity, computability, and logical correctness testing capability via animated simulation. The OPM model also defined the architecture and logic of the SEP and the Control Panel(CP) - two essential parts incorporated into the existing telerobotic simulator. Simulated subsystems were introduced to enable simulation of setup, shutdown and off-nominal scenarios as defined by the OPM model. The SEP has several automation options, catches erroneous actions and ensures preconditions for each step are satisfied. The CP interfaces has several functions, including automating failure recovery and showing automated customize procedures to restore system to pre-failure configuration. This thesis considered only one application and further applications are needed to demonstrate the utility of OPM in the broader HFE domain. Nonetheless, the advantages of OPM over traditional TA methods demostrated OPM as a viable alternative to current HFE practices.
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2017.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 208-211).
2017-01-01T00:00:00ZUsing a systems-theoretic approach to analyze cyber attacks on cyber-physical systemshttp://hdl.handle.net/1721.1/110143
Using a systems-theoretic approach to analyze cyber attacks on cyber-physical systems
Whyte, David L., 1967-
With increased Internet connectivity and the advent of the industrial Internet, cyber-physical systems are increasingly being targeted by cyber attacks. Unlike, cyber attacks on IT networks, successfully compromising a cyber-physical environment takes considerably more time, motivation, expertise, and operational costs to the adversary. This thesis explores how a systems-theoretic approach, the Systems-Theoretic Accident Model and Processes (STAMP), can be used by an organization to complement intelligence-driven models of intrusion analysis to provide both additional insight and prioritize defensive countermeasures in order to guard against cyber-physical attacks and compromises. Specifically, in this thesis we analyze two real-world use cases of well publicized cyber-physical attacks using traditional intelligence-driven models of intrusion analysis as well as apply the Causal Analysis based on STAMP (CAST) model on one of the use cases. The STAMP/CAST based analysis afforded us deeper insights into the system causal factors that led to the successful compromise. In turn, this allowed for the generation of specific recommendations to safeguard the cyber-physical systems within the network in order to increase the overall organizational security posture. This included a recommendation to modify the existing organizational structure (i.e., the addition of a Security Operations Centre function) such that clearly defined security roles and responsibilities could be effectively implemented thus significantly improving an organization's ability to respond to cyber attacks.
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, 2017.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 113-118).
2017-01-01T00:00:00Z